Testicular leukocytes: what are they doing?

Leukocytes, specifically macrophages, lymphocytes and mast cells, are found within the testes of most, if not all, mammals. In some species (for example, rats, mice and humans), the number of 'resident' testicular macrophages, in particular, is quite considerable. However, reproductive biologists are only beginning to explore the characteristics and possible biological significance of these cells. As in other tissues, the testicular leukocytes are involved in immunological surveillance, immunoregulation and tissue remodelling. They are implicated in the mechanisms that make the testis a particularly successful site for tissue transplantation in some experimental animals. Moreover, recent studies have demonstrated that the testicular macrophages have specific trophic effects on Leydig cell development and steroidogenesis. In turn, the development and functions of the testicular leukocyte population are clearly influenced by the testicular environment, and especially by the Leydig cells and Sertoli cells. These data indicate an important role for leukocytes in testicular homeostasis. Balanced against this beneficial role is the fact that these cells possess the potential to damage testicular function in conditions of immune activation, as their inflammatory and cytotoxic activities may disrupt the normal environment of the testis. The importance of the testicular leukocytes to normal and abnormal testicular function is evident. The challenge for future research is to define the details of this relationship.

This article has been cited by other articles:

				M.S. Theas, C. Rival, S. Jarazo-Dietrich, P. Jacobo, V.A. Guazzone, and L. Lustig Tumour necrosis factor-{alpha} released by testicular macrophages induces apoptosis of germ cells in autoimmune orchitis Hum. Reprod., August 1, 2008; 23(8): 1865 - 1872. [Abstract] [Full Text] [PDF]

				Y Okuma, K Saito, A E O'Connor, D J Phillips, D M de Kretser, and M P Hedger Reciprocal regulation of activin A and inhibin B by interleukin-1 (IL-1) and follicle-stimulating hormone (FSH) in rat Sertoli cells in vitro J. Endocrinol., April 1, 2005; 185(1): 99 - 110. [Abstract] [Full Text] [PDF]

				J. B. Sundstrom, D. M. Little, F. Villinger, J. E. Ellis, and A. A. Ansari Signaling through Toll-Like Receptors Triggers HIV-1 Replication in Latently Infected Mast Cells J. Immunol., April 1, 2004; 172(7): 4391 - 4401. [Abstract] [Full Text] [PDF]

				N. Melaine, A. Ruffault, N. Dejucq-Rainsford, and B. Jegou Experimental inoculation of the adult rat testis with Sendai virus: effect on testicular morphology and leukocyte population Hum. Reprod., August 1, 2003; 18(8): 1574 - 1579. [Abstract] [Full Text] [PDF]

				D. A. Hume, I. L. Ross, S. R. Himes, R. T. Sasmono, C. A. Wells, and T. Ravasi The mononuclear phagocyte system revisited J. Leukoc. Biol., October 1, 2002; 72(4): 621 - 627. [Abstract] [Full Text] [PDF]

				A. L. Asirvatham and B. C. Bruot Cell-Cell Interactions in the Testis of Adjuvant-Induced Arthritic Rat J Androl, July 1, 2002; 23(4): 491 - 497. [Abstract] [Full Text] [PDF]

				O. Gerdprasert, M.K. O'Bryan, D.J. Nikolic-Paterson, K. Sebire, D.M. de Kretser, and M.P. Hedger Expression of monocyte chemoattractant protein-1 and macrophage colony-stimulating factor in normal and inflamed rat testis Mol. Hum. Reprod., June 1, 2002; 8(6): 518 - 524. [Abstract] [Full Text] [PDF]

				C. Habasque, F. Aubry, B. Jegou, and M. Samson Study of the HIV-1 receptors CD4, CXCR4, CCR5 and CCR3 in the human and rat testis Mol. Hum. Reprod., May 1, 2002; 8(5): 419 - 425. [Abstract] [Full Text] [PDF]

				Y. O. Lukyanenko, J.-J. Chen, and J. C. Hutson Production of 25-Hydroxycholesterol by Testicular Macrophages and Its Effects on Leydig Cells Biol Reprod, March 1, 2001; 64(3): 790 - 796. [Abstract] [Full Text]

				H.B. S. Ariyaratne, N. Mills, J. I. Mason, and S.M.L. C. Mendis-Handagama Effects of Thyroid Hormone on Leydig Cell Regeneration in the Adult Rat Following Ethane Dimethane Sulphonate Treatment Biol Reprod, October 1, 2000; 63(4): 1115 - 1123. [Abstract] [Full Text]

				F. Aubry, C. Habasque, A.-P. Satie, B. Jégou, and M. Samson Expression and Regulation of the CC-Chemokine Monocyte Chemoattractant Protein-1 in Rat Testicular Cells in Primary Culture Biol Reprod, May 1, 2000; 62(5): 1427 - 1435. [Abstract] [Full Text]

				M. K. O'Bryan, S. Schlatt, D. J. Phillips, D. M. de Kretser, and M. P. Hedger Bacterial Lipopolysaccharide-Induced Inflammation Compromises Testicular Function at Multiple Levels in Vivo Endocrinology, January 1, 2000; 141(1): 238 - 246. [Abstract] [Full Text] [PDF]

				A. Meinhardt, M. Bacher, C. Metz, R. Bucala, N. Wreford, H. Lan, R. Atkins, and M. Hedger Local Regulation of Macrophage Subsets in the Adult Rat Testis: Examination of the Roles of the Seminiferous Tubules, Testosterone, and Macrophage-Migration Inhibitory Factor Biol Reprod, August 1, 1998; 59(2): 371 - 378. [Abstract] [Full Text]